Auto and aircraft seat cover fabric comprising regenerative natural fibers

ABSTRACT

A novel pure natural and regenerative automotive and aircraft upholstery fabric made from linen and blends of linen and cotton, bamboo, wool and/or viscose with physiological and fastness properties comparable with those of currently-used materials and meeting all the requirements of the automobile and aircraft industry.

This disclosure relates to upholstery fabrics for use in transport seating and to methods of making them.

STATE OF THE ART

The fabrics used in the interiors of automobiles and aircraft are generally produced exclusively from artificial fibers, which in turn are derived from petroleum feedstocks. These include materials such as polyester (PES) and polypropylene. The production of such fibers involves the generation of considerable volumes of carbon (CO₂). In addition, they are poorly biodegradable, which means that environmentally-conscious disposal is a problem. Finally, the prices of such materials are highly dependent on the price of crude oil, which has tended to increase over time, meaning that the prices of such fibers also tend to increase in line with this.

TECHNICAL PROBLEM AND ITS SOLUTION

This invention of a new and purely natural upholstery fabric for transport seating, particularly automobile, train and aircraft seats, now aims to replace previous petroleum-based synthetic fiber substrates such as polyester and polypropylene with pure or blended natural, regenerative raw materials.

This invention, therefore, provides an automobile or aircraft seat upholstery made exclusively of environmentally-friendly renewable natural fibers, characterized in that the major component is linen. The aim is to use long-fiber flax fibers and blends of linen with cotton, bamboo, wool and/or viscose (regenerated cellulose fiber), which are renewable natural fiber mixtures. The mixing ratios are between 1% to max. 100% by weight of pure linen.

Preference is given to mixtures of 50% linen and 50% cotton, bamboo and/or viscose-filament whereby the mixing ratio between cotton and/or other natural cellulosic fibers is each between 0% and 50% cotton and 0% up to max. 50% viscose—filament where the proportion of cotton can be replaced up to max. 40% by viscose filament.

In addition to physiological use advantages of natural comfort in modern motor vehicles and aircraft, ecologically-friendly biodegradability and the possibility of natural recovery of the raw material, the much-debated CO₂ generation is reduced considerably in the production of the upholstery fabric hereinabove described. Studies (see e.g. Grafic: Nova Institute 2007; Eyerer & Reinhardt 2000, Pless 2001, BaFa 2006, Ifeu 2005 resp. SachsenLeinen 2006b and DaimlerChrysler 1997) show that the cumulative energy demand (CED) of natural fibers such as flax and hemp is reduced by up to 83% compared to that of petroleum-derived and glass fibers, as a result of the natural growth.

The independence of the natural fiber raw material from the extreme price fluctuations of petroleum-derived plastics such as polyester and polypropylene as a result of the fluctuations in oil prices, leads to further significant economical and cost advantages.

Another object of the invention is to provide a natural regenerated product as automobile and airplane upholstery fabric which in its physiological as well as colour fastness properties is equal to or better than those of the prior art, and that meets or improves the high performance demands of the automotive and aircraft industries.

Primarily the following requirements must be met or improved:

-   -   1.) All abrasion resistance and tensile strength tested         according to Martindale strength test as the most stringent test     -   2.) Elongation test     -   3.) Heat light fastness tested according to the FAKRA test         method (the most stringent light fastness test)     -   4.) Flame resistance     -   5.) Rubbing fastness dry and wet     -   6.) Staining resistance     -   7.) Mold- and decomposition resistance (antibacterial finishing)

The economics of production and the product price have to be as good as, or better than, those of petroleum-based synthetic car upholstery fabrics.

To meet these requirements, new developments have been made to make this new product suitable for the automobile and aircraft industry so that the product of the invention is brought to a new state of the art. These are now described in more detail.

Optimization of Natural Fiber Blends

For automotive and aircraft upholstery fabrics produced from pure natural fibers, high standards with respect to fiber staple length, fiber quality, fiber surface and spin twisting must be met to meet the performance requirements such as tensile strength and abrasion resistance in the use of automobile and aircraft seats (Martindale test must meet minimum requirement of 50.000 revolutions).

It is desired to achieve a maximum surface quality of high quality fibers in zs combination with mixtures of fibers with smooth surfaces such as viscose filaments and the optimization of these with respect to their use. Such mixtures primarily include linen, cotton, bamboo, and viscose/modal fiber as filaments. The minimum requirements are fabric weights between 100 and 700 g/m² (preferably between 200 and 600 g/m²).

Spinning and Weaving

The automotive upholstery surface structures and the fabric weights must comply with the requirements and demands of the automotive industry and match each other by selected yarn counts (fineness), optimal spin rotation (twist effect), weaves such as Panama, twill, satin, etc., density in warp and weft of the natural fiber blends and mixing ratios. The minimum requirements are:

-   -   Fabric width: between 1 m and 3 m, preferably between 1.30 and         1.60 m     -   Fabric weight: between 100 and 700 g/m2, preferably between 200         and 600 g/m2     -   Density/10 cm: warp between 50 and 600, preferably between 100         and 500         weft between 50 and 300, preferably between 100 and 200     -   yarn fineness:         -   warp 20-200 tex, preferably 40-60 tex         -   weft linen 50-300, preferably 100-200 tex             Here are 3 examples:

Weaving Blend: linen/cotton 50/50 sample 1: Fabric width: 1.55 m Fabric weight: 320 g/m² Density/10 cm: warp: 155 weft: 152 Yarn fineness warp: Cotton Nm 20 (=50 tex) weft: Linen Nm 9.6 (=103 tex) Weaving Blend: linen/Cotton 50/50 sample 2: Fabric width: 1.53 m Fabric weight: 430 g/m² Density/10 cm: warp: 321 weft: 146 Yarn fineness: warp: Cotton 50 tex weft: Linen 170 tex Weaving Blend: Linen/Cotton 50/50 sample 3: Fabric width: 1.52 m Fabric weight: 375 g/m² Density/10 cm: warp: 416 weft: 138 Yarn fineness: warp: Cotton 50 tex weft: Linen 110 tex Weaving Blend: Linen/Cotton 50/50 bleached sample 4: Fabric width: 1.49 m Fabric weight: 440 g/m² Yarn turning: Cotton Nm 20/1 (=50 tex), turns: −612/m Linen Nm 6.8 (=140 tex), turns −309/m Knitted goods can also be employed.

Pretreatment

A further step in achieving the desired requirements is the use of a state-of-the-art pretreatment for linen and linen/cellulose mixtures, such as desizing, demineralization, bleaching, as well as a special mercerization process to reduce the fiber abrasion behavior and to increase the required abrasion fastness according to the Martindale test (minimum 50.000 revolutions).

The mercerization is carried out with highly concentrated caustic soda liquor and some alkyl sulfonate under fabric tension, for example, by the following method:

-   Recipe:     -   8.0 ml/kg alkylsulfonate     -   743.0 ml/kg caustic soda 30° Be -   Treatment:     -   60 sec. immersion time and thereafter at least 2 min batching         time under fabric tension     -   rinsing: at 25° C./70° C./25° C. each 3 min immersion time     -   neutralization: with Sirrix™ NE fl. (Clariant)

An additional advantageous effect of the mercerization is that the dyestuff build-up and the through-dyeing, particularly for deep shades such as black, is significantly improved.

First sample: blend sample cotton/linen 50/50 bleached, non-mercerized

Second sample: blend sample cotton/linen 50/50 bleached and mercerized.

Dyeing Process

A natural fiber automotive upholstery fabric made from linen and blends with cotton or other cellulosic fibers such as bamboo and viscose must be dyed with dyestuffs quite different from those used for polyester. While polyester must be dyed with disperse dyestuffs, this inventive new product is primarily dyed with reactive, substantive, vat or sulphur dyestuffs. For reasons of the high fastness requirements for this intended use, reactive dyes are preferred for this application.

Another important feature of this invention is that the high light-fastness and high heat temperature light-fastness (several times FAKRA-heat temperature light-fastness) required by the automobile industry, achievable by the use, for example, of disperse dyestuffs on PES, can now also be achieved by this invention by using specifically selected reactive dyestuffs on natural cellulose fibers such as linen and its above-mentioned blends with cotton and other mixtures with cellulose fibers such as viscose and bamboo.

Another important aspect of this invention is, therefore, a careful selection of suitable reactive dyestuffs with high light fastness as individual dyestuffs and as components for high light fastness trichromatic blends from existing reactive dyestuff ranges.

All single and multiple anchor reactive dyestuffs, as well as sulphur and vat dyes, may be used. In the reactive dyestuff field, the following reactive components can be used:

dichlorotriazine, fluorochloropyrimidine (FCP), dichloroquinoxaline, mono-fluorotriazine, 2× monofluorotriazine, monochlorotriazine+vinylsulfone, trifluoropyrimidine, monofluorotriazine/monochlorotriazine+vinylsulfone, fluorochloropyrimidine/monochlorotriazine+vinyl sulfone, vinyl sulfone, or 2× vinylsulfone, monochlorotriazine, 2× monochloro-triazine, monochlorotriazine modified, trichloropyrimidine.

Preference is given to specifically selected reactive dyestuffs based on single/multiple anchor fluorochlorpyrimidine as the main reactive so component.

In order to achieve the light- and FAKRA-high temperature fastness (dependent on the degree of dyestuff fixation) on the one hand, and, on the other hand, a highly productive economic dyeing process, the dyeing process must be optimised.

The following suitable dyeing processes are preferred:

-   1.) Cold Pad Batch Process (CPB) as semi continuous process -   2.) E-control process (new development of A. Monforts (ICI,     EP 081016) completely continuous process. -   3.) Pad Dry Thermofix Process, completely continuous process -   4.) Pad Dry Steam Process, completely continuous process -   5.) Chemical Pad Steam Process, completely continuous process -   6.) Exhaustion Process, discontinuous process in piece -   7.) Exhaustion Process, discontinuous process in yarn

The weights of fabric in automotive upholstery goods are between 100 and 700 g/m2, preferably between 300 and 600 g/m2 and most preferably about 400 g/m2. When using qualities of around 400 g/m2, it must be ensured, on the one hand, that a very good dye penetration is achieved, and on the other hand, that the most economical dyeing process is used. In order to reconcile both requirements, there exists, in addition, on the part of the chemistry, the possibility of using special dyeing liquor additives such as 10-60 g/l, preferably 20-50 g/l of a polymerization product based on acrylamide to support the dyestuff diffusion in order to achieve an improved dyestuff penetration of the goods.

For the best possible thorough dyeing, the process and the liquor recipe were optimized for the highest possible dyestuff diffusion.

The invention is illustrated by the following dyeing samples:

EXAMPLE 1

Linen/cotton automotive upholstery fabric, about 430 g/m2, weaving sample 2 hereinabove described, desized, demineralized, bleached and mercerized, is padded in a semi-continuous cold pad batch process with the following recipe for a black dyeing

-   -   45 g/l Reactive Orange CI RO 69     -   25 g/l Reactive Rubinol CI RR 171     -   70 g/l Reactive Blue CI RB 209     -   50 g/l urea (solvent for dyestuff)     -   1 ml/l nonionic wetting agent     -   1 ml/l sequestration agent

An alkaline liquor of the following composition

-   -   50 ml/l Sodium silicate 38° Be     -   12 ml/l caustic soda 36° Be         in liquor ratio of 1:4 is supplied continuously to the dye         liquor by means of a dosage pump, and with this in the padder         the fabric is padded. Liquor temperature: 20° C.

After this process, the fabric is batched cold 4 hours and washed off as follows:

It is rinsed in cold soft water, soaped in boiling water containing 2 ml/l Ladipur™ RSK liquid detergent, rinsed in hot soft water, then in cold soft water, neutralized with acetic acid and dried.

This gives a deep, level and good dyed-through black dyeing with perfect heat light fastness (FAKRA 3 fold grade note 8 blue scale, Xenon note 8 blue scale) and good wet fastness properties.

EXAMPLE 2

Linen/cotton—automotive upholstery fabric, 320 g/m², weaving sample 1 hereinabove described, desized, demineralized, bleached, mercerized is dyed in a newly-developed, fully continuous E-control process of the textile machine company A. Monforts, Mönchengladbach, using the following recipe:

-   -   45 g/l Reactive Orange CI RO 69     -   25 g/l Reactive Rubinol CI RR 171     -   70 g/l Reactive Blue CI RB 209     -   100 g/l urea     -   1 ml/l wetting agent (nonionic)

An alkali liquor containing 24 g/l soda ash in liquor ratio 1:4 with liquor temperature at 20° C. is separately led to the dyeing padder by means of a dosage pump.

The fabric is dyed at the E-control unit consisting of an IR pre-dryer and a hot-flue constant air humidity of 25% and 75% air and a chamber temperature of 125° C. (fabric temperature is approx. 69° C.). The whole process consists of the steps of: padding, predrying at IR pre-dryer and complete drying at hot-flue. The complete dyestuff fixation takes place at the same time.

Afterwards the dyed fabric is washed off as follows:

-   -   Cold rinsing in soft water     -   In boiling soft water soaping with 2 ml/l Ladipur™ RSK liquid         detergent     -   hot rinsing in soft water     -   cold rinsing in soft water     -   neutralization with acetic acid     -   drying

This gives a deep, level and good through-dyed black dyeing with perfect light fastnesses (FAKRA heat light fastness 3 fold, note 8 in blue scale, note 4.5 in grey scale, XENON perfect as well, note 8 in blue scale) and another good wet- and rubbing fastness.

EXAMPLE 3

Linen/cotton—automotive upholstery fabric, 320 g/m2, weaving fabric 1 as hereinabove described, desized, demineralized, bleached, mercerized, is dyed in a semi-continuous cold pad batch process using the following recipe:

-   -   3.9 g/l Reactive Orange CI RO 69     -   2.8 g/l Reactive Rubinol CI RR 171     -   5.0 g/l Reactive Blue CI RB 209     -   1 ml/l nonionic wetting agent     -   1 ml/l sequestration agent

An alkali liquor in liquor ratio 1:4 of the following recipe

-   -   50 ml/l sodium silicate 38° Be     -   5 ml/l caustic soda 36° Be         is separately added by means of a dosage pump.

Dye liquor temperature: 20° C.

The dyed fabric is then batched cold for 4 hours and washed off as follows:

-   -   cold rinsing in soft water     -   boiled soft water soaping with 2 ml/l Ladipur™ RSK liq.         detergent     -   hot rinsing in soft water     -   cold rinsing in soft water     -   neutralization with acetic acid     -   drying

This gives a level, good through-dyed light grey dyeing with very good wet- and rubbing fastnesses and a good XENON light fastness with note 6.5 in blue scale. The multiple FAKRA heat light fastness is good, but not quite so high a standard as achieved in the black dyeings hereinabove exemplified.

EXAMPLE 4

Linen/cotton—automotive upholstery fabric, 320 g/m2, weaving sample 1 hereinabove described, desized, demineralized, bleached and mercerized is dyed in the Monforts equipment of Example 2, using the following recipe:

-   -   3.9 g/l Reactive Orange CI RO 69     -   2.8 g/l Reactive Rubinol CI RR 171     -   5.0 g/l Reactive Blue CI RB 209     -   1.0 ml/l wetting agent (nonionic)

An alkaline liquor with 14 g/l soda ash in a liquor ratio of 1:4, liquor temperature: 20° C., is separately led to the dyeing trough by means of a dosage pump.

The fabric is dyed at the E-control unit consisting of IR pre-dryer and hot-flue constantly with a climate of 25% humidity and 75% air and a chamber temperature of 125° C. (fabric temperature is approximately 69° C.)

The whole continuous process is as follows: padding, pre-drying at IR pre-dryer and complete drying at hot-flue, and the dyestuff fixation takes place at the same time.

The dyed fabric is then washed off as follows:

-   -   cold rinsing in soft water     -   in boiling soft water soaping with 2 ml detergent from type         Ladipur™ RSK liq. detergent     -   hot rinsing in soft water     -   cold rinsing in soft water     -   neutralization with acetic acid     -   drying

The result is a deep, level and good through-dyed light grey dyeing with very good wet- and rubbing fastnesses, with a XENON light fastness note 6.5 in blue scale, and a high-standard multiple FAKRA heat light fastness although not quite to the standard of the black dyeing hereinabove exemplified.

EXAMPLE 5

Linen/cotton 50/50, 430 g/m² (weaving sample 4 hereinabove described) bleached and high twisted as black dyeing is dyed in a cold pad batch process. This new pattern is woven with in exhaust process-bleached, high twisted yarns. As a result, the fabric could withstand 60,000 rpm on the Martindale abrasion test.

EXAMPLE 6

Fabric: 100% linen, about 120 g/m2, bleached.

Continuous dyeing process compared: cold pad batch process against E-control process Monforts

Recipe Cold Pad Batch process:

-   -   32 g/l Reactive Orange CI RO 69     -   50 ml/l sodium silicate 38° Bé     -   15 ml/l caustic soda 36° Bé     -   Batching time: 8 hours, followed by washing off and drying

Recipe E-control process:

-   -   32 g/l Reactive Orange CI RO 69     -   10 g/l soda ash     -   2.5 ml/l caustic soda 36° Bé

The fabric is dyed at the E-control unit as hereinabove described, consisting of padder, infra-red pre-dryer and hot-flue unit with a constant climate of 25% humidity and 75% air and a chamber temperature of 125° C. (fabric temperature is approximately 69° C.). This results in doing so in the simultaneous achievement of pre-drying, complete drying dyestuff fixation, after padding. The dyed fabric is then washed off, as hereinabove exemplified.

Both processes give perfect, even deep and brilliant pure linen dyeing, in which the depth of dyeing is virtually identical.

In a further trial of the same methods and conditions on 100% linen of the same fabric with a deep navy shade with 90 g/l dyestuff, two perfect, even deep and brilliant pure linen dyeings are obtained. In this case, the dyeing of the E-control process was 13% deeper.

Finishing Process

For finishing, the now mercerized and dyed upholstery fabric product of linen/cotton must be made to meet the existing requirement profiles of the automobile and aircraft industry in three steps, as follows:

-   -   1.) Mildew- and mold protection (microbacterial protection).     -   2.) Flame resistance     -   3.) Abrasion- and scour resistance     -   4.) Antipilling     -   5.) Stain resistance

The steps 1), 2) and 3) are carried out in that order, with the option of combining steps 2) and 3).

FINISHING EXAMPLE STEP 1 Microbacterial Protection

The rotting and mold resistance finishing is done in a separate process with a bactericide of the type Sanitize™ 2724 (ex Sanitized AG, Switzerland) which is a pyrithione zinc compound at a treatment concentration of 0.5-2% based on the fabric weight. The application is carried out by padding or spraying, followed by drying at 100-150° C. The treatment takes place directly after the dyeing and drying processes. Because this is a pure natural product, rotting and mold resistance finishing is essential.

FINISHING EXAMPLE STEP 2 Flame Retardant Finishing

The flame retardant finishing is achieved, using phosphate- or silicone products, preferably phosphate products.

Use concentration: 100 up to max. 500 g/l, preferably 200-300 g/l

The liquor is padded on and subsequently dried at 100-150° C. The treatment is carried out separately after the application of the anti-bacterial product, or it may optionally be combined with the abrasion resistance finishing of step 3). By optimization of the products and their concentrations, the good dry and wet rubbing fastnesses of the reactive dyeing are not impaired.

FINISHING EXAMPLE STEP 3

-   Recipe:     -   100 g/l polyacrylate-based development product     -   5 g/l fluorocarbon product (nonionic)     -   0.3 g/l wetting agent (anionic)

The addition of softener products is also possible. Padder application, wet pick up 80%, 1 min at 150° C. effectively dried and condensed.

The abrasion resistance of the black dyed sample was tested in the Martindale test method according to EN ISO 12947-1 with 12 Kpa at 5.000, 10.000, 20.000 and 60.000 RPM.

The 100% natural automotive upholstery sample could withstand undamaged the test up to 60.000 RPM.

The surprising aspect of the entire finishing operation is that the physiological and fastness results obtained after dyeing and drying, primarily the FAKRA and xenon light fastnesses, the rubbing fastness and the abrasion resistance according to the Martindale tests were not impaired but improved, so that the end-product meets the high requirements of the automobile, bus and aircraft industry. Moreover, this can be done with a natural product in place of a petroleum-derived synthetic product.

Combined Advantages of the New Invention:

-   1.) An automotive and aircraft seat upholstery fabric consisting of     pure vegetable natural products that meets the high physiological,     fastness and safety related requirements of the aircraft and     automobile industry. -   2.) The product is 100% biodegradable and therefore is highly     environmentally friendly. -   3.) It consist of 100% natural renewable raw materials with high     sustainability. -   4.) The CO₂ costs for the production of this natural product,     calculated according to the cumulative energy demand (CED), is 83%     lower than that of the production of petroleum-derived products or     glass fibres. -   5.) The fabric price is unaffected by the price fluctuations of the     world petroleum market, and is thus stable and predictable. -   6.) Physiological benefits of pure natural fibers. -   7.) Car seat fibres build up no electrostatic charge. 

1. An automotive or aircraft seat upholstery fabric made exclusively from renewable and environmental-friendly natural fiber material wherein the major component is linen.
 2. Automotive or aircraft seat upholstery fabric according to claim 1, characterized in that it consists of linen and additionally incorporated cellulose fibers such as cotton, bamboo and/or admixed viscose.
 3. Automotive or aircraft seat upholstery fabric according to claim 1, characterized in that it consists of at least 50% linen and the balance consists of cotton, bamboo and/or viscose filament in mixing ratio of cotton and/or other natural cellulose fibers each between 0 and 50% and viscose filament 0 up to maximum 50%.
 4. Automotive or aircraft seat upholstery fabric according to claim 1, characterized in that it consist of 50% linen and 50% cotton wherein up to 40% of cotton is replaced by viscose filament.
 5. Automotive or aircraft seat upholstery fabric according to claim 1, characterized in that each one of these fabrics has a weight between 100 and 700 g/m², preferably between 200 and 600 g/m².
 6. Automotive or aircraft seat upholstery fabric according to claim 1, characterized in that the fabric is washed, desized, demineralized, bleached and mercerized.
 7. Automotive or aircraft seat upholstery fabric according to claim 1, characterized in that the fabric is semi- or fully continuously dyed in pieces, or discontinuously by exhaustion dyeing as yarn or pieces.
 8. Automotive or aircraft seat upholstery fabric according of claim 7, characterized in that there are used high lightfast mono- or multifunctional reactive dyestuffs used as single dyestuffs and as components of a trichromy capable of meeting all fastness requirements of the automobile industry such as rubbing- and wet fastnesses.
 9. Automotive or aircraft seat upholstery fabric according to claim 7, characterized in that the fabric is dyed with a dye liquor in which is added 10-60 g/l of an acrylamide-based polymerization product for improving the through-dyeing and the dyestuff diffusion.
 10. Automotive or aircraft seat upholstery fabric according to claim 9, characterized in that it is padded with an additional finishing liquor containing 50-200 g/l of a special nature polyacrylate, 2-15 g/l of a fluorocarbon product (non-ionic) and from 0.2-2 g/l anionic wetting agent and optionally a softener product and then dried for 1 min at 150° C. and fixed.
 11. Automotive or aircraft seat upholstery fabric according to claim 1, characterized in that this fabric is padded or sprayed with a bactericide against decay and mold in a separate process and afterwards dried.
 12. Automotive or aircraft seat upholstery fabric according to claim 1, characterized in that this fabric is finished with a flame-resistant finishing based on a phosphate compound which impairs neither the light fastness (FAKRA) nor the rubbing fastness. 